Abstract
Radiant heat gain severely endangers thermal comfort and dramatically increases building energy consumptions in a tropical outdoor urban environment. To rapidly evaluate outdoor thermal features, this paper presents a three-dimensional integrated numerical model to assess building surface temperature and mean radiant temperature (MRT) in typical outdoor industrial environments of Singapore. For proper accounting of solar irradiance and radiant heat fluxes, Perez all-weather model and finite volume discrete ordinates method (fvDOM) are integrated into numerical code. Under the climate conditions of Singapore, i.e., light wind and intense solar irradiance, the model adopts a daily-average convection coefficient to simplify air dynamics to solve the surface energy balance equation so that the model efficiency can be significantly improved. Surface thermal load computed using the model has been validated by the on-site measurement for a contemporary and a matured industrial building on two sunny days. By comparing simulated and measured results, the corresponding coefficient of determination (R2) and the refined index of agreement (RIA) are respectively > 0.99 and > 0.8 to indicate that the model agrees well with the measurement. Also, the model is used to predict the MRT map around the industrial environment and to demonstrate that tree shading reduces mean MRT of 6.3 °C for daily-average and 13.29 °C at noon in a street canyon under a 25% greenery coverage ratio.
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•Rapidly assess building surface temperature and mean radiant temperature.•Tropical industrial environments.•Intense solar irradiance and low wind speed.•Daily-average convection coefficient based on measurement.•Calculated surface temperature has been validated by the on-site measurement.